Acoustic Definition and 174 Threads

Homework Statement The acousitc wave from a sperical explosion is sometimes represented by a function: p = 0 for t < r/c p = B / r * exp [ - (t-r/c) / t0 ] for t > r/c (or equal) a) Does this represent a possible soltion for the wave equation? b) Find the corresponding velocity...

Homework Statement One organ pipe open on both ends and one organ pipe open at one end and closed at the other are tuned on the same fundamental tone with frequency f = 264 Hz. a)How long is each pipe? b) Determine the first three harmonics of each pipe. c) There is an organ pipe open at both...

I am currently trying to incorporate the sensing of tool wear as part of my research, which is an investigation into an experimental manufacturing process that is probably most similar to milling. I have already been making use of force data, but would like to utilize acoustic data as well...

Hi everybody, In chapter 10 of Kittel's "Introduction to Solid State Physics" it is said that the zeros of the dielectric functions determine the frequency of the longitudinal modes of oscillation, \epsilon(\omega_L) = 0, Eq. (17). Am I missing something or this is actually an "unproved claim"...

I would like to measure the relative amplitudes (energy levels) of several specific frequencies in a noise field. I thought of attaching capacitive microphones to tubes that would resonate at those frequencies. I've visited hundreds of web sites that invariably give equations for...

Assume that a narrow layer of the sun just below the photosphere is modeled by an isothermal layer of neutral hydrogen and helium at 8000K below which is a fully convective layer with adiabatic sound velocity increasing linearly as a function of depth with a scale length of 100 km a.) use the...

Hello! Sorry, I don't have much of a formal education, but am an amateur singer (female, age 66, tenor) who experienced a BIG surprise during one of our choral concerts a few weeks ago. While a fellow tenor was singing a solo (Gounod "Sanctus"), I heard distinct undertones (fourths). I was so...

I am studying acoustic wave reflection. The boundary conditions of acoustics are continuity of pressure and normal particle velocity. Can anyone tell me if these boundary conditions are completely independent? (Since the pressure and particle velocity are in phase, I would believe they are not...

Hi, I'm not sure if this is the correct forum, or even the correct website but you all seem to know what you're talking about! I make native american style flutes, and have recently become interested in the physics of sound and soundwaves, etc. I've done well in my research, but have come...

Hello All, I have become interested in the study of nonlinear acoustic/longitudinal wave effects and came across this interesting article on HowStuffWorks.com which talks about Acoustic levitation: http://science.howstuffworks.com/acoustic-levitation2.htm On the above link, they post the...

Are there certain materials that reflect acoustic waves diffusely? Would the material need to have large (visible) surface features to produce this kind of reflection or can the surface be smooth? Are there materials that reflect acoustic waves in accordance with Lambert's cosine law?

Defining the period measured by a moving observer relative to a stationary source as T=t(n)-t(n-1) where t(n) and t(n-1) represent the times when two successive wavecrests are received respectively, the theory of the Doppler Effect leads zero and negative periods in the case of sonic and...

say i have a 1.5m diameter and 7m lond pipe, blocked of at one end and leading into a 2.8m diameter horizontaly laid manifold (so that effectively you have one small pipe branching of another large pipe), the pipes are filled with water. In order to calculate the resonance frequencies, i would...

Hi, I'm making an AUV and need to design my own acoustic modem. Now, after hours of research I found these PDFs (attached). In theory, can I remove the signal generator from XXXXPinger.pdf, add a DTMF encoder and then use a build the transducer as described in bender2.pdf to transmit the...

http://www.aip.org/pnu/2006/split/779-1.html Diagram: http://aip.org/png/2006/260.htm Paper: http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRLTAO000096000021215504000001&idtype=cvips&gifs=yes

Where does the sound difference between acoustic and their electric counterparts come from, even when playing the same sustained note (i.e., same frequency)?

the problems is that: two loudspeakers, A and B, radiate sound uniformly in all directions in air at 20 degree C. The acoustic power output from A is 8x10^-4 W, and from B it is 6x10^-5 W. Both loudspeakers are vibrating in phase at a frequency of 172 Hz. a) Determine the difference in...

I need help with a question about acoustic resonance. Sound of wavelength 20cm is produced at one end of a 32 cm long tube. Is it possible for resonance to be produced?

Is it possible to correlate the atmospheric acoustic vs. ground seismic waveforms from a charge detonation? Are there any physicists on this forum that recognise the acoustic and seismic waveform signatures from a charge detonation? Acoustic, Seismic wave function equation: \psi (x,t) = A...

I'm looking for data on "acoustic noise" produced regularly by the earth, nothing man-made. In particular I'm looking for noise sources outside of the normal range of human hearing (20Hz-20kHz). Of course there are numerous terrestial noise sources, such as earthquake tremors, but those aren't...

Can someone point towards some useful information for me about the frequency dependence (over the audio frequency range) on acoustic mirrors, acoustic waveguides/horns and interfenece and diffraction effects please? Thanks

Acoustic Interferometer: Interference with the Quincke Tube. See here: http://www.mip.berkeley.edu/physics/B+35+05.html The diagram and physics suggests that acoustic interference is achieved through this simple device. Makes sense to me. However, with the potential for destructive...

I'm working on a project that involves 'acoustic radiation pressure'.. This means that an acoustic wave can exert a net force on some object, along it's propagation-direction.. if the object was a plate, it would look somewhat like this: ...... | ----||--wave--> |->Force...

http://www.princeton.edu/~globsec/publications/pdf/9_3altmann.pdf